Initial cleanup in ReadHardware
Straightening ReadHardware workflow
Adapted testsuite
Filter out storage only devices. bnc#841170, fate#316090

Broadcom multifunctional devices use private flags which can be used for
distinguishing device capabilities.
Removed dead code / comments
Continuing cleanup
Refactoring: Splitting ReadHardware
Refactoring: ReadHardware - replaced some of internal variables

to ease further splitting into separate method
ReadHardware: cleanup - replaced a Builtins' method using ruby native
ReadHardware: splitted more code filtering detected devices
Renamed an internal variable.
Replaced obsolete logging in new helper method.
Dropped dead code
Moved variables definition closer to its usage.
Constantized ReadHardware's local variables
Updated changelog
ReadHardware: splitted hw detection confirmation
ReadHardware: Fixed doc